To answer each question in order, Homebrew, Fire Emblem Awakening and Windows. Yes, something that can export and import saves like save manager in the 3ds folder on your 3ds sd card. Download the nightly build if you don't want to decompress and recompress the saves. If you want the features of the regular version, you will need to decompress your save files with FEAST. Make sure your saves are on your computer. Open FireEditor, and use it to open one of the chapter files. Make your edits. If you used the nightly builds, put the saves in the folder where you exported the save to on your sd card. If you used the official release, recompress your saves with FEAST. Put them on your SD card in the place where they were exported to. MAKE SURE THEY HAVE THE SAME NAME! Import the save, load up fire emblem awakening, profit!